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Song J, Fransen PPKH, Bakker MH, Wijnands SPW, Huang J, Guo S, Dankers PYW. The effect of charge and albumin on cellular uptake of supramolecular polymer nanostructures. J Mater Chem B 2024. [PMID: 38682307 DOI: 10.1039/d3tb02631k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/01/2024]
Abstract
Intracellular delivery of functional biomolecules by using supramolecular polymer nanostructures has gained significant interest. Here, various charged supramolecular ureido-pyrimidinone (UPy)-aggregates were designed and formulated via a simple "mix-and-match" method. The cellular internalization of these UPy-aggregates in the presence or absence of serum proteins by phagocytic and non-phagocytic cells, i.e., THP-1 derived macrophages and immortalized human kidney cells (HK-2 cells), was systematically investigated. In the presence of serum proteins the UPy-aggregates were taken up by both types of cells irrespective of the charge properties of the UPy-aggregates, and the UPy-aggregates co-localized with mitochondria of the cells. In the absence of serum proteins only cationic UPy-aggregates could be effectively internalized by THP-1 derived macrophages, and the internalized UPy-aggregates either co-localized with mitochondria or displayed as vesicular structures. While the cationic UPy-aggregates were hardly internalized by HK-2 cells and could only bind to the membrane of HK-2 cells. With adding and increasing the amount of serum albumin in the cell culture medium, the cationic UPy-aggregates were gradually taken up by HK-2 cells without anchoring on the cell membranes. It is proposed that the serum albumin regulates the cellular internalization of UPy-aggregates. These results provide fundamental insights for the fabrication of supramolecular polymer nanostructures for intracellular delivery of therapeutics.
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Affiliation(s)
- Jiankang Song
- Institute for Complex Molecular Systems, Eindhoven University of Technology, PO Box 513, 5600 MB, The Netherlands.
- Department of Biomedical Engineering, Laboratory for Cell and Tissue Engineering, Eindhoven University of Technology, PO Box 513, 5600 MB, The Netherlands
- Department of Biomedical Engineering, Laboratory of Chemical Biology, Eindhoven University of Technology, PO Box 513, 5600 MB, The Netherlands
| | - Peter-Paul K H Fransen
- Institute for Complex Molecular Systems, Eindhoven University of Technology, PO Box 513, 5600 MB, The Netherlands.
- Department of Biomedical Engineering, Laboratory of Chemical Biology, Eindhoven University of Technology, PO Box 513, 5600 MB, The Netherlands
| | - Maarten H Bakker
- Institute for Complex Molecular Systems, Eindhoven University of Technology, PO Box 513, 5600 MB, The Netherlands.
- Department of Biomedical Engineering, Laboratory of Chemical Biology, Eindhoven University of Technology, PO Box 513, 5600 MB, The Netherlands
| | - Sjors P W Wijnands
- Institute for Complex Molecular Systems, Eindhoven University of Technology, PO Box 513, 5600 MB, The Netherlands.
- Department of Biomedical Engineering, Laboratory of Chemical Biology, Eindhoven University of Technology, PO Box 513, 5600 MB, The Netherlands
| | - Jingyi Huang
- Institute for Complex Molecular Systems, Eindhoven University of Technology, PO Box 513, 5600 MB, The Netherlands.
- Department of Biomedical Engineering, Laboratory of Chemical Biology, Eindhoven University of Technology, PO Box 513, 5600 MB, The Netherlands
| | - Shuaiqi Guo
- Institute for Complex Molecular Systems, Eindhoven University of Technology, PO Box 513, 5600 MB, The Netherlands.
| | - Patricia Y W Dankers
- Institute for Complex Molecular Systems, Eindhoven University of Technology, PO Box 513, 5600 MB, The Netherlands.
- Department of Biomedical Engineering, Laboratory for Cell and Tissue Engineering, Eindhoven University of Technology, PO Box 513, 5600 MB, The Netherlands
- Department of Biomedical Engineering, Laboratory of Chemical Biology, Eindhoven University of Technology, PO Box 513, 5600 MB, The Netherlands
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Bakker MH, de Smit MJ, Valentijn A, Visser A. Oral health assessment in institutionalized elderly: a scoping review. BMC Oral Health 2024; 24:272. [PMID: 38402181 PMCID: PMC10893687 DOI: 10.1186/s12903-024-04025-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2023] [Accepted: 02/14/2024] [Indexed: 02/26/2024] Open
Abstract
When elderly become frail and in need for complex care, they can no longer live independently at home and may be admitted to nursing homes. Various studies have shown that oral health in this population is remarkably poor, which may lead to distressing situations and impacts quality of life. A variety of definitions or descriptions for oral health is used. Without a uniform parameter, it is impossible to determine whether oral health in institutionalized elderly is actually improving or deteriorating over time, as well as the effect of (preventive) interventions. In search for an adequate and clinically applicable parameter to determine oral health in this specific patient group, this scoping review aims to give an overview of the currently used parameters for determining oral health in institutionalized elderly. Ninety different parameters were identified, and 50 parameters were solely used by one study. Only 4 parameters were frequently used (in > 20 studies). The relevance of these parameters for this specific patient group is discussed. To aid the planning and commissioning of future research and patient care, there is an urgent need for an adequate and uniform parameter for oral health determination in institutionalized elderly.
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Affiliation(s)
- M H Bakker
- Department of Gerodontology, Center for Dentistry and Oral Hygiene, University Medical Center Groningen and University of Groningen, Groningen, The Netherlands.
| | - M J de Smit
- Department of Gerodontology, Center for Dentistry and Oral Hygiene, University Medical Center Groningen and University of Groningen, Groningen, The Netherlands
| | - A Valentijn
- Department of Gerodontology, Center for Dentistry and Oral Hygiene, University Medical Center Groningen and University of Groningen, Groningen, The Netherlands
| | - A Visser
- Department of Gerodontology, Center for Dentistry and Oral Hygiene, University Medical Center Groningen and University of Groningen, Groningen, The Netherlands
- Department of Gerodontology, College of Dental Sciences, Radboud University Nijmegen Medical Center, Nijmegen, The Netherlands
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de Smit MJ, Bakker MH, Tams J, Vissink A, Visser A. [Whether or not to remove root remnants in frail older adults?]. Ned Tijdschr Tandheelkd 2023; 130:17-24. [PMID: 36637014 DOI: 10.5177/ntvt.2023.01.22082] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
Many frail older adults have a poor oral health: unrestorable broken teeth and root remnants with open root canals, commonly associated with periapical and periodontal inflammation, are often seen. Improving oral health in this growing group of frail older adults is a considerable challenge for dental care professionals. Dentists are often uncertain how to deal with root remnants and unrestorable broken teeth in psychogeriatric and/or medically compromised frail older adults. Decisions about the extraction or retention of root remnants should not only be made on the basis of preventing pain and inflammation, but also on the course of disease, life expectancy, cooperation, laws and regulations and other factors that are an issue in geriatric patients but not in regular (healthy) patients. To help oral health care professionals in their treatment choice for this complex patient group, a decision tree was developed in which both root and patient-related factors were included.
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Bakker MH, Vissink A, Raghoebar GM, Peters LL, Visser A. [General health, healthcare costs and dental care use of elderly with differing oral status]. Ned Tijdschr Tandheelkd 2022; 129:87-93. [PMID: 35133739 DOI: 10.5177/ntvt.2022.02.21115] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Cross-sectional studies have shown that elderly with a natural dentition or implant-retained overdenture have better general health outcomes than elderly with conventional dentures. It is not known whether these findings would be confirmed in longitudinal studies of such groups of elderly. Therefore, in this study a large group of elderly (aged 75 and over) with a natural dentition (n = 143,199), an implant-retained overdenture (n = 6,503) or conventional denture (n=18,420) were followed over a period of 8 years. Elderly with conventional dentures had chronic conditions more often, used more medication and had higher healthcare costs. Remarkably, the general health outcomes of elderly with an implant-retained overdenture declined over the period of 8 years. At the time the implant-retained overdenture was placed, their general health profile seemed comparable to that of elderly with a natural dentition, but as time progressed it declined to the level of elderly with conventional dentures.
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Besseling PJ, Mes T, Bosman AW, Peeters JW, Janssen HM, Bakker MH, Fledderus JO, Teraa M, Verhaar MC, Gremmels H, Dankers PYW. The in‐vitro biocompatibility of ureido‐pyrimidinone compounds and polymer degradation products. Journal of Polymer Science 2021. [DOI: 10.1002/pol.20210072] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Paul J. Besseling
- Department of Nephrology and Hypertension University Medical Center Utrecht Utrecht The Netherlands
| | | | | | | | - Henk M. Janssen
- SyMO‐Chem BV Den Dolech 2 Eindhoven The Netherlands
- Department of Biomedical Engineering, Laboratory of Chemical Biology Eindhoven University of Technology Eindhoven The Netherlands
| | - Maarten H. Bakker
- Institute for Complex Molecular Systems Eindhoven University of Technology Eindhoven The Netherlands
| | - Joost O. Fledderus
- Department of Nephrology and Hypertension University Medical Center Utrecht Utrecht The Netherlands
| | - Martin Teraa
- Department of Nephrology and Hypertension University Medical Center Utrecht Utrecht The Netherlands
| | - Marianne C. Verhaar
- Department of Nephrology and Hypertension University Medical Center Utrecht Utrecht The Netherlands
| | - Hendrik Gremmels
- Department of Nephrology and Hypertension University Medical Center Utrecht Utrecht The Netherlands
| | - Patricia Y. W. Dankers
- Department of Biomedical Engineering, Laboratory of Chemical Biology Eindhoven University of Technology Eindhoven The Netherlands
- Institute for Complex Molecular Systems Eindhoven University of Technology Eindhoven The Netherlands
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Bakker MH, Vissink A, Spoorenberg SLW, Wynia K, Visser A. Self-reported oral health problems and the ability to organize dental care of community-dwelling elderly aged ≥75 years. BMC Oral Health 2020; 20:185. [PMID: 32615975 PMCID: PMC7331152 DOI: 10.1186/s12903-020-01175-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2020] [Accepted: 06/25/2020] [Indexed: 12/21/2022] Open
Abstract
Background It is unclear how many community-dwelling elderly (≥75 years) experience oral health problems (e.g. pain, dry mouth, chewing problems) and how they manage their dental care needs. This study aimed to assess self-reported oral health problems in elderly who are frail or have complex care needs, and their ability to organize dental care when reporting oral pain. Methods Three thousand five hundred thirty-three community-dwelling elderly participating in the “Embrace” project were asked to complete questionnaires regarding oral status and oral health problems. Frailty was assessed with the Groningen Frailty Indicator (GFI). Intermed for Elderly Self-Assessment (IM-E-SA) was used to determine complexity of care needs. Next, elderly who reported oral pain were interviewed about their oral pain complaints, their need for dental care, and their ability to organize and receive dental care. For statistical analyses Chi2-tests and the one-way ANOVA were used. Results One thousand six hundred twenty-two elderly (45.9%) completed the questionnaires. Dry mouth (11.7%) and oral pain (6.2%) were most frequently reported. Among the elderly reporting oral pain, most were registered at a local dentist and could go there when needed (84.3%). Robust elderly visited the dentist independently (87%), frail (55.6%) and complex (26.9%) elderly more often required assistance from caregivers. Conclusions Dry mouth and oral pain are most reported oral health problems among community-dwelling elderly. Elderly with complex care needs report most oral health problems. In case an elderly seeks dental treatment to alleviate an oral pain complaint, most elderly in this study were able to organize dental care and transport to the dentist. Frail and complex elderly often need assistance from caregivers to visit the dentist. Therefore caretakers should keep in mind that when frailty progresses, visiting a dentist may become more and more difficult and the risk for poor oral health increases.
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Affiliation(s)
- M H Bakker
- Department of Maxillofacial Surgery, University of Groningen, University Medical Center Groningen, PO Box 30.001, NL-9700, RB, Groningen, The Netherlands.
| | - A Vissink
- Department of Maxillofacial Surgery, University of Groningen, University Medical Center Groningen, PO Box 30.001, NL-9700, RB, Groningen, The Netherlands
| | - S L W Spoorenberg
- Department of Health Sciences, Community and Occupational Medicine, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands
| | - K Wynia
- Department of Health Sciences, Community and Occupational Medicine, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands
| | - A Visser
- Department of Maxillofacial Surgery, University of Groningen, University Medical Center Groningen, PO Box 30.001, NL-9700, RB, Groningen, The Netherlands.,Department of Geriatric Dentistry, Dental School, Center for Dentistry and Oral Hygiene, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands
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Visser A, Bakker MH, Niesten D, Janssens L, Palmers E, Duyck J, Bots-van 't Spijker PC, Bruers JJM, van der Maarel-Wierink CD, Vissink A. [A view on collective oral care for frail older people: united we stand]. Ned Tijdschr Tandheelkd 2019; 126:673-678. [PMID: 31840679 DOI: 10.5177/ntvt.2019.12.19066] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Oral health in frail older people is often poor. There are a number of reasons for this, such as increased morbity and decreased motivation for (self) care. Good oral health is, however, very important. Studies have revealed poor oral health to cause or aggravate several medical and psychological problems. Illness and medication can, in turn, damage oral health. Oral health among the elderly should therefore be carefully monitored and maintained. This requires multidisciplinary and interprofessional collaboration on the part of healthcare professionals and others involved. Such collaboration is now still very limited; hardly anything has been written about how such collaboration in the area of oral care for frail older people should or could be organised. This article provides an overview of the possibilities and the relevant factors in the area of oral care for the elderly in promoting collaboration among healthcare professionals and others involved. All of this is under the banner of 'united we stand'.
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Mol EA, Lei Z, Roefs MT, Bakker MH, Goumans M, Doevendans PA, Dankers PYW, Vader P, Sluijter JPG. Injectable Supramolecular Ureidopyrimidinone Hydrogels Provide Sustained Release of Extracellular Vesicle Therapeutics. Adv Healthc Mater 2019; 8:e1900847. [PMID: 31559704 DOI: 10.1002/adhm.201900847] [Citation(s) in RCA: 51] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2019] [Revised: 08/23/2019] [Indexed: 12/15/2022]
Abstract
Extracellular vesicles (EVs) are small vesicles secreted by cells and have gained increasing interest as both drug delivery vehicles or as cell-free therapeutics for regenerative medicine. To achieve optimal therapeutic effects, strategies are being developed to prolong EV exposure to target organs. One promising approach to achieve this is through EV-loaded injectable hydrogels. In this study, the use of a hydrogel based on ureido-pyrimidinone (UPy) units coupled to poly(ethylene glycol) chains (UPy-hydrogel) is examined as potential delivery platform for EVs. The UPy-hydrogel undergoes a solution-to-gel transition upon switching from a high to neutral pH, allowing immediate gelation upon administration into physiological systems. Here, sustained EV release from the UPy-hydrogel measured over a period of 4 d is shown. Importantly, EVs retain their functional capacity after release. Upon local administration of fluorescently labeled EVs incorporated in a UPy-hydrogel in vivo, EVs are still detected in the UPy-hydrogel after 3 d, whereas in the absence of a hydrogel, EVs are internalized by fat and skin tissue near the injection site. Together, these data demonstrate that UPy-hydrogels provide sustained EV release over time and enhance local EV retention in vivo, which could contribute to improved therapeutic efficacy upon local delivery and translation toward new applications.
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Affiliation(s)
- Emma A. Mol
- Department of CardiologyLaboratory of Experimental CardiologyUniversity Medical Center Utrecht Utrecht 3584 The Netherlands
- Laboratory of Cardiovascular Cell BiologyDepartment of Cell and Chemical BiologyLeiden University Medical Center Leiden 2333ZA The Netherlands
| | - Zhiyong Lei
- Department of CardiologyLaboratory of Experimental CardiologyUniversity Medical Center Utrecht Utrecht 3584 The Netherlands
| | - Marieke T. Roefs
- Department of CardiologyLaboratory of Experimental CardiologyUniversity Medical Center Utrecht Utrecht 3584 The Netherlands
| | - Maarten H. Bakker
- Institute for Complex Molecular SystemsDepartment of Biomedical EngineeringLaboratory of Chemical BiologyEindhoven University of Technology 5600 MB Eindhoven The Netherlands
| | - Marie‐José Goumans
- Laboratory of Cardiovascular Cell BiologyDepartment of Cell and Chemical BiologyLeiden University Medical Center Leiden 2333ZA The Netherlands
| | - Pieter A. Doevendans
- Department of CardiologyLaboratory of Experimental CardiologyUniversity Medical Center Utrecht Utrecht 3584 The Netherlands
- UMC Utrecht Regenerative Medicine CenterUniversity Medical Center Utrecht 3584CT The Netherlands
- CMH NL‐HI Utrecht 3584CX The Netherlands
| | - Patricia Y. W. Dankers
- Institute for Complex Molecular SystemsDepartment of Biomedical EngineeringLaboratory of Chemical BiologyEindhoven University of Technology 5600 MB Eindhoven The Netherlands
| | - Pieter Vader
- Department of CardiologyLaboratory of Experimental CardiologyUniversity Medical Center Utrecht Utrecht 3584 The Netherlands
- Laboratory of Clinical Chemistry and HaematologyUniversity Medical Center Utrecht Utrecht 3584 The Netherlands
| | - Joost P. G. Sluijter
- Department of CardiologyLaboratory of Experimental CardiologyUniversity Medical Center Utrecht Utrecht 3584 The Netherlands
- UMC Utrecht Regenerative Medicine CenterUniversity Medical Center Utrecht 3584CT The Netherlands
- University Utrecht Utrecht 3508TC The Netherlands
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Tseng CC, Wenker S, Bakker MH, Kraaijeveld AO, Dankers PY, Seevinck PR, Smink J, Kimmel S, van Slochteren FJ, Chamuleau SA. Active tracked intramyocardial catheter injections for regenerative therapy with real-time MR guidance: feasibility in the porcine heart. EUROINTERVENTION 2019; 15:e336-e339. [DOI: 10.4244/eij-d-17-01081] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Bakker MH, van Rooij E, Dankers PYW. Controlled Release of RNAi Molecules by Tunable Supramolecular Hydrogel Carriers. Chem Asian J 2018; 13:3501-3508. [PMID: 29858562 DOI: 10.1002/asia.201800582] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2018] [Revised: 05/27/2018] [Indexed: 11/06/2022]
Abstract
Local, sustained release and presentation of RNAi therapeutics can be achieved with hydrogel delivery systems. Here we show the development of a supramolecular hydrogel into a local RNAi delivery system. By careful material design, two simple but effective strategies are introduced to obtain controlled release of two classes of RNAi therapeutics, that is, microRNA and antimiR. It was shown that the release of microRNA could be regulated using cholesterol-modification for interaction with the supramolecular hydrogel. Non-modified antimiR release could be controlled via supramolecular introduction of positively charged additive molecules into the supramolecular hydrogel. In this way, either the cholesterol-modification on the drug or the charge introduction into the hydrogel provides handles for controlled RNAi therapy.
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Affiliation(s)
- Maarten H Bakker
- Institute for Complex Molecular Systems, Department of Biomedical Engineering, Laboratory of Chemical Biology, Eindhoven University of Technology, 5600 MB, Eindhoven, The Netherlands
| | - Eva van Rooij
- Hubrecht Institute, KNAW, and University Medical Center Utrecht, 3584 CT, Utrecht, The Netherlands
| | - Patricia Y W Dankers
- Institute for Complex Molecular Systems, Department of Biomedical Engineering, Laboratory of Chemical Biology, Eindhoven University of Technology, 5600 MB, Eindhoven, The Netherlands
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Bakker MH, Tseng CCS, Keizer HM, Seevinck PR, Janssen HM, Van Slochteren FJ, Chamuleau SAJ, Dankers PYW. MRI Visualization of Injectable Ureidopyrimidinone Hydrogelators by Supramolecular Contrast Agent Labeling. Adv Healthc Mater 2018; 7:e1701139. [PMID: 29658175 DOI: 10.1002/adhm.201701139] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2017] [Revised: 01/03/2018] [Indexed: 11/07/2022]
Abstract
Information about the in vivo location, shape, degradation, or erosion rate of injected in situ gelating hydrogels can be obtained with magnetic resonance imaging (MRI). Herein, an injectable supramolecular ureidopyrimidinone-based hydrogel (UPy-PEG) is functionalized with a modified Gadolinium(III)-DOTA complex (UPy-Gd) for contrast enhanced MRI. The contrast agent is designed to supramolecularly interact with the hydrogel network to enable high-quality imaging of this hydrogel. The applicability of the approach is demonstrated with successful visualization of the Gd-labeled UPy-PEG hydrogel after targeted intramyocardial catheter injection in a pig heart.
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Affiliation(s)
- Maarten H. Bakker
- Institute for Complex Molecular Systems and Laboratory of Chemical Biology; Eindhoven University of Technology; P. O. Box 513 5600 MB Eindhoven The Netherlands
| | - Cheyenne C. S. Tseng
- Department of Cardiology; Division Heart and Lungs; University Medical Center Utrecht; P. O. Box 85500 3584 CX Utrecht The Netherlands
| | - Henk M. Keizer
- SyMO-Chem B.V.; Den Dolech 2 5612 AZ Eindhoven The Netherlands
| | - Peter R. Seevinck
- Image Sciences Institute; University Medical Center Utrecht; Heidelberglaan 100 3584 CX Utrecht The Netherlands
| | - Henk M. Janssen
- SyMO-Chem B.V.; Den Dolech 2 5612 AZ Eindhoven The Netherlands
| | - Frebus J. Van Slochteren
- Department of Cardiology; Division Heart and Lungs; University Medical Center Utrecht; P. O. Box 85500 3584 CX Utrecht The Netherlands
| | - Steven A. J. Chamuleau
- Department of Cardiology; Division Heart and Lungs; University Medical Center Utrecht; P. O. Box 85500 3584 CX Utrecht The Netherlands
| | - Patricia Y. W. Dankers
- Institute for Complex Molecular Systems and Laboratory of Chemical Biology; Eindhoven University of Technology; P. O. Box 513 5600 MB Eindhoven The Netherlands
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Bakker MH, Grillaud M, Wu DJ, Fransen PPKH, de Hingh IH, Dankers PYW. Cholesterol Modification of an Anticancer Drug for Efficient Incorporation into a Supramolecular Hydrogel System. Macromol Rapid Commun 2018; 39:e1800007. [PMID: 29806084 DOI: 10.1002/marc.201800007] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2018] [Revised: 04/18/2018] [Indexed: 12/14/2022]
Abstract
Treatment of cancer in the peritoneal cavity may be improved with macroscale drug delivery systems that offer control over intraperitoneal concentration of chemotherapeutic agents. Currently, suitable drug carriers to facilitate a sustained release of small hydrophilic drugs such as mitomycin C are lacking. For this purpose, a pH-responsive supramolecular hydrogel based on ureido-pyrimidinone (UPy) chemistry is utilized here. In order to provide a sustained release profile, a lipophilicity-increasing cholesterol conjugation strategy is proposed that enhances affinity between the modified drug (mitomycin-PEG24 -cholesterol, MPC) and the hydrophobic compartments in the UPy gel. Additional advantages of cholesterol conjugation include improved chemical stability and potency of mitomycin C. In vitro the tunability of the system to obtain optimal effective concentrations over time is demonstrated with a combinatorial treatment of mitomycin C and MPC in one UPy hydrogel delivery system.
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Affiliation(s)
- Maarten H Bakker
- Institute for Complex Molecular Systems and Laboratory of Chemical Biology, Eindhoven University of Technology, P.O. Box 513, 5600, MB, Eindhoven, The Netherlands
| | - Maxime Grillaud
- Institute for Complex Molecular Systems and Laboratory of Chemical Biology, Eindhoven University of Technology, P.O. Box 513, 5600, MB, Eindhoven, The Netherlands
| | - Dan Jing Wu
- Institute for Complex Molecular Systems and Laboratory of Chemical Biology, Eindhoven University of Technology, P.O. Box 513, 5600, MB, Eindhoven, The Netherlands
| | - Peter-Paul K H Fransen
- Institute for Complex Molecular Systems and Laboratory of Chemical Biology, Eindhoven University of Technology, P.O. Box 513, 5600, MB, Eindhoven, The Netherlands
| | - Ignace H de Hingh
- Department of Surgical Oncology, Catharina Cancer Institute, 5623, EJ, Eindhoven, The Netherlands
| | - Patricia Y W Dankers
- Institute for Complex Molecular Systems and Laboratory of Chemical Biology, Eindhoven University of Technology, P.O. Box 513, 5600, MB, Eindhoven, The Netherlands
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Eding JEC, Vink M, Bakker MH, Versteeg D, Kooijman L, Dankers PYW, Van Rooij E. P96Supramolecular hydrogel for local cardiac delivery of antimiR therapeutics. Cardiovasc Res 2018. [DOI: 10.1093/cvr/cvy060.059] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- JEC Eding
- Hubrecht Institute, Utrecht, Netherlands
| | - M Vink
- Hubrecht Institute, Utrecht, Netherlands
| | - M H Bakker
- Eindhoven University of Technology, Eindhoven, Netherlands
| | - D Versteeg
- Hubrecht Institute & University Medical Center Utrecht, Utrecht, Netherlands
| | - L Kooijman
- Hubrecht Institute, Utrecht, Netherlands
| | - PYW Dankers
- Eindhoven University of Technology, Eindhoven, Netherlands
| | - E Van Rooij
- Hubrecht Institute & University Medical Center Utrecht, Utrecht, Netherlands
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Mol E, Lei Z, Bakker MH, Vader P, Schiffelers RM, Dankers PYW, Chamuleau SAJ, Doevendans PA, Goumans MJ, Sluijter JP. 202Slow release of cardiac progenitor cell-derived extracellular vesicles from a pH-switchable hydrogel. Cardiovasc Res 2018. [DOI: 10.1093/cvr/cvy060.152] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- E Mol
- University Medical Center Utrecht, Experimental Cardiology, Utrecht, Netherlands
| | - Z Lei
- University Medical Center Utrecht, Experimental Cardiology, Utrecht, Netherlands
| | - M H Bakker
- Eindhoven University of Technology, Institute for Complex Molecular Systems, Eindhoven, Netherlands
| | - P Vader
- University Medical Center Utrecht, Experimental Cardiology and Laboratory of Clinical Chemistry and Haematology, Utrecht, Netherlands
| | - R M Schiffelers
- University Medical Center Utrecht, Laboratory of Clinical Chemistry and Haematology, Utrecht, Netherlands
| | - PYW Dankers
- Eindhoven University of Technology, Institute for Complex Molecular Systems, Eindhoven, Netherlands
| | - SAJ Chamuleau
- University Medical Center Utrecht, Experimental Cardiology, Utrecht, Netherlands
| | - P A Doevendans
- University Medical Center Utrecht, Experimental Cardiology, Utrecht, Netherlands
| | - M J Goumans
- Leiden University Medical Center, Molecular Cell Biology, Leiden, Netherlands
| | - J P Sluijter
- University Medical Center Utrecht, Experimental Cardiology, Utrecht, Netherlands
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15
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Bakker MH, Vissink A, de Baat C, Visser A. [Medicaments and oral healthcare 6. Oral side effects of -medications commonly used by older people]. Ned Tijdschr Tandheelkd 2017; 124:645-652. [PMID: 29257837 DOI: 10.5177/ntvt.2017.12.17167] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
In the coming decades the western world will experience a double ageing of its population; there will be an increase in both the number of older people and the average age. The increase in life expectancy will also mean more and more older people who suffer from multiple systemic diseases that are treated with medications. At this moment, 45% of those over 65 use 5 or more medications and 20% of those over 75 use as many as 10 or more. The more medications used, the greater the risk of side effects and therefore oral side effects, like symptoms of dry mouth or the development of candidiasis, angioedema, gingival hyperplasia, lichenoid reaction of the oral mucosa, dysgeusia, halitosis and osteonecrosis. Considering the wide range of oral side effects, it is important for dentists to be well aware of the medications being used by older patients as well as having a thorough knowledge of their oral side effects.
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16
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Bakker MH, Lee CC, Meijer EW, Dankers PYW, Albertazzi L. Multicomponent Supramolecular Polymers as a Modular Platform for Intracellular Delivery. ACS Nano 2016; 10:1845-1852. [PMID: 26811943 DOI: 10.1021/acsnano.5b05383] [Citation(s) in RCA: 74] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Supramolecular polymers are an emerging family of nanosized structures with potential use in materials chemistry and medicine. Surprisingly, application of supramolecular polymers in the field of drug delivery has received only limited attention. Here, we explore the potential of PEGylated 1,3,5-benzenetricarboxamide (BTA) supramolecular polymers for intracellular delivery. Exploiting the unique modular approach of supramolecular chemistry, we can coassemble neutral and cationic BTAs and control the overall properties of the polymer by simple monomer mixing. Moreover, this platform offers a versatile approach toward functionalization. The core can be efficiently loaded with a hydrophobic guest molecule, while the exterior can be electrostatically complexed with siRNA. It is demonstrated that both compounds can be delivered in living cells, and that they can be combined to enable a dual delivery strategy. These results show the advantages of employing a modular system and pave the way for application of supramolecular polymers in intracellular delivery.
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Affiliation(s)
| | - Cameron C Lee
- Novartis Institutes for Biomedical Research , 100 Technology Square, Cambridge, Massachusetts 02139, United States
| | | | | | - Lorenzo Albertazzi
- Institute for Bioengineering of Catalonia (IBEC) , Carrer de Baldiri Reixac 15-21, 08028 Barcelona, Spain
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17
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Abstract
Ureidopyrimidinone-based polymers in solution provide a new platform for intracellular drug delivery.
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Affiliation(s)
- Maarten H. Bakker
- Institute for Complex Molecular Systems
- Eindhoven University of Technology
- The Netherlands
- Laboratory of Chemical Biology
- Eindhoven University of Technology
| | - Roxanne E. Kieltyka
- Institute for Complex Molecular Systems
- Eindhoven University of Technology
- The Netherlands
- Laboratory of Chemical Biology
- Eindhoven University of Technology
| | - Lorenzo Albertazzi
- Institute for Complex Molecular Systems
- Eindhoven University of Technology
- The Netherlands
- Laboratory of Chemical Biology
- Eindhoven University of Technology
| | - Patricia Y. W. Dankers
- Institute for Complex Molecular Systems
- Eindhoven University of Technology
- The Netherlands
- Laboratory of Chemical Biology
- Eindhoven University of Technology
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18
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Hessels AM, Chabosseau P, Bakker MH, Engelen W, Rutter GA, Taylor KM, Merkx M. eZinCh-2: A Versatile, Genetically Encoded FRET Sensor for Cytosolic and Intraorganelle Zn(2+) Imaging. ACS Chem Biol 2015; 10:2126-34. [PMID: 26151333 PMCID: PMC4577962 DOI: 10.1021/acschembio.5b00211] [Citation(s) in RCA: 72] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Zn(2+) plays essential and diverse roles in numerous cellular processes. To get a better understanding of intracellular Zn(2+) homeostasis and the putative signaling role of Zn(2+), various fluorescent sensors have been developed that allow monitoring of Zn(2+) concentrations in single living cells in real time. Thus far, two families of genetically encoded FRET-based Zn(2+) sensors have been most widely applied, the eCALWY sensors developed by our group and the ZapCY sensors developed by Palmer and co-workers. Both have been successfully used to measure cytosolic free Zn(2+), but distinctly different concentrations have been reported when using these sensors to measure Zn(2+) concentrations in the ER and mitochondria. Here, we report the development of a versatile alternative FRET sensor containing a de novo Cys2His2 binding pocket that was created on the surface of the donor and acceptor fluorescent domains. This eZinCh-2 sensor binds Zn(2+) with a high affinity that is similar to that of eCALWY-4 (Kd = 1 nM at pH 7.1), while displaying a substantially larger change in emission ratio. eZinCh-2 not only provides an attractive alternative for measuring Zn(2+) in the cytosol but was also successfully used for measuring Zn(2+) in the ER, mitochondria, and secretory vesicles. Moreover, organelle-targeted eZinCh-2 can also be used in combination with the previously reported redCALWY sensors to allow multicolor imaging of intracellular Zn(2+) simultaneously in the cytosol and the ER or mitochondria.
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Affiliation(s)
- Anne M. Hessels
- Laboratory
of Chemical Biology and Institute of Complex Molecular Systems (ICMS),
Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, The Netherlands
| | - Pauline Chabosseau
- Section
of Cell Biology and Functional Genomics, Division of Medicine, Imperial College London, London, United Kingdom
| | - Maarten H. Bakker
- Laboratory
of Chemical Biology and Institute of Complex Molecular Systems (ICMS),
Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, The Netherlands
| | - Wouter Engelen
- Laboratory
of Chemical Biology and Institute of Complex Molecular Systems (ICMS),
Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, The Netherlands
| | - Guy A. Rutter
- Section
of Cell Biology and Functional Genomics, Division of Medicine, Imperial College London, London, United Kingdom
| | - Kathryn M. Taylor
- Breast
Cancer Molecular Pharmacology Group, School of Pharmacy and Pharmaceutical
Sciences, Cardiff University, Cardiff, United Kingdom
| | - Maarten Merkx
- Laboratory
of Chemical Biology and Institute of Complex Molecular Systems (ICMS),
Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, The Netherlands
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19
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Pape ACH, Bakker MH, Tseng CCS, Bastings MMC, Koudstaal S, Agostoni P, Chamuleau SAJ, Dankers PYW. An Injectable and Drug-loaded Supramolecular Hydrogel for Local Catheter Injection into the Pig Heart. J Vis Exp 2015:e52450. [PMID: 26132631 PMCID: PMC4544772 DOI: 10.3791/52450] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Regeneration of lost myocardium is an important goal for future therapies because of the increasing occurrence of chronic ischemic heart failure and the limited access to donor hearts. An example of a treatment to recover the function of the heart consists of the local delivery of drugs and bioactives from a hydrogel. In this paper a method is introduced to formulate and inject a drug-loaded hydrogel non-invasively and side-specific into the pig heart using a long, flexible catheter. The use of 3-D electromechanical mapping and injection via a catheter allows side-specific treatment of the myocardium. To provide a hydrogel compatible with this catheter, a supramolecular hydrogel is used because of the convenient switching from a gel to a solution state using environmental triggers. At basic pH this ureido-pyrimidinone modified poly(ethylene glycol) acts as a Newtonian fluid which can be easily injected, but at physiological pH the solution rapidly switches into a gel. These mild switching conditions allow for the incorporation of bioactive drugs and bioactive species, such as growth factors and exosomes as we present here in both in vitro and in vivo experiments. The in vitro experiments give an on forehand indication of the gel stability and drug release, which allows for tuning of the gel and release properties before the subsequent application in vivo. This combination allows for the optimal tuning of the gel to the used bioactive compounds and species, and the injection system.
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Affiliation(s)
- A C H Pape
- Institute for Complex Molecular Systems, Department of Biomedical Engineering, Laboratory of Chemical Biology, Eindhoven University of Technology
| | - Maarten H Bakker
- Institute for Complex Molecular Systems, Department of Biomedical Engineering, Laboratory of Chemical Biology, Eindhoven University of Technology
| | - Cheyenne C S Tseng
- Department of Cardiology, Division Heart and Lungs, Interuniversity Cardiology Institute of the Netherlands (ICIN), University Medical Center Utrecht
| | - Maartje M C Bastings
- Institute for Complex Molecular Systems, Department of Biomedical Engineering, Laboratory of Chemical Biology, Eindhoven University of Technology
| | - Stefan Koudstaal
- Department of Cardiology, Division Heart and Lungs, Interuniversity Cardiology Institute of the Netherlands (ICIN), University Medical Center Utrecht
| | - Pierfrancesco Agostoni
- Department of Cardiology, Division Heart and Lungs, Interuniversity Cardiology Institute of the Netherlands (ICIN), University Medical Center Utrecht
| | - Steven A J Chamuleau
- Department of Cardiology, Division Heart and Lungs, Interuniversity Cardiology Institute of the Netherlands (ICIN), University Medical Center Utrecht
| | - Patricia Y W Dankers
- Institute for Complex Molecular Systems, Department of Biomedical Engineering, Laboratory of Chemical Biology, Eindhoven University of Technology;
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20
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Beynen AC, Baas JC, Hoekemeijer PE, Kappert HJ, Bakker MH, Koopman JP, Lemmens AG. Faecal bacterial profile, nitrogen excretion and mineral absorption in healthy dogs fed supplemental oligofructose. J Anim Physiol Anim Nutr (Berl) 2002; 86:298-305. [PMID: 12452971 DOI: 10.1046/j.1439-0396.2002.00386.x] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
In a cross-over trial, five healthy dogs were fed a dry food without or with 1% (w/w) oligofructose to assess any oligofructose-induced effects on the faecal bacterial profile, nitrogen excretion and mineral absorption. The diets were given for a period of 3 weeks. Oligofructose feeding significantly raised the number of Bifidobacteria, Streptococci and Clostridia in faeces. The numbers of faecal anaerobic and aerobic bacteria were raised after ingestion of oligofructose. The faecal pH was unchanged. There was no effect of oligofructose feeding on the route of nitrogen excretion which was associated with a lack of effect on faecal ammonium and urinary urea excretion. It is suggested that the absence or presence of an effect of oligofructose on urinary and faecal nitrogen excretion depends on the background composition of the diet, in particular the content of non-digestible, fermentable carbohydrates. In the diets used, the content of non-digestible, fermentable carbohydrates was not measured. Both apparent magnesium and calcium absorption were significantly raised by oligofructose feeding, but phosphorus absorption was unaffected. The data presented may contribute to the qualification of the use of oligofructose in dog foods.
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Affiliation(s)
- A C Beynen
- Department of Nutrition, Faculty of Veterinary Medicine, Utrecht University, The Netherlands.
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21
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Bonaventure P, Umans L, Bakker MH, Cras P, Langlois X, Luyten WH, Megens AA, Serneels L, Van Leuven F, Leysen JE. Humanization of mouse 5-hydroxytryptamine1B receptor gene by homologous recombination: in vitro and in vivo characterization. Mol Pharmacol 1999; 56:54-67. [PMID: 10385684 DOI: 10.1124/mol.56.1.54] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
We replaced the coding region of the murine 5-hydroxytryptamine (5-HT)1B receptor by the human 5-HT1B receptor using homologous recombination in embryonic stem cells and generated and characterized homozygous transgenic mice that express only the human (h) 5-HT1B receptor. The distribution patterns of h5-HT1B and murine (m) 5-HT1B receptor mRNA and binding sites in brain sections of transgenic and wild-type mice were identical as measured by in situ hybridization histochemistry and radioligand receptor autoradiography. When measured in parallel under identical conditions, the h5-HT1B receptor expressed in mouse brain had the same pharmacological characteristics as that in human brain. Stimulation by 5-HT1B agonists of [35S]guanosine-5'-O-(3-thio)triphosphate binding in brain sections demonstrated the functional coupling of the h5-HT1B receptor to G proteins in mouse brain. In tissue slices from various brain regions, electrically stimulated [3H]5-HT release was not modified by 5-HT1B agonists in tissue from either transgenic and wild-type mice; a 5-HT1B antagonist enhanced electrically stimulated [3H]5-HT release in wild-type mouse brain, but was ineffective in the transgenics. The centrally active 5-HT1A/5-HT1B agonist RU24969 induced hypothermia but did not increase locomotor activity in the transgenic mice. The ineffectiveness of RU24969 in the transgenic mice could be due to the lower affinity of the compound for the h5-HT1B receptor compared with the m5-HT1B receptor. The present study demonstrates a complete replacement of the mouse receptor by its human receptor homolog and a functional coupling to G proteins. However, modulation of [3H]5-HT release could not be shown. Furthermore, behavioral effects were not clearly observed, which may be due to a lack of appropriate tools.
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Affiliation(s)
- P Bonaventure
- Department of Biochemical Pharmacology, Janssen Research Foundation, Beerse, Belgium.
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22
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Snel J, Bakker MH, Heidt PJ. Quantification of antigen-specific immunoglobulin A after oral booster immunization with ovalbumin in mice mono-associated with segmented filamentous bacteria or Clostridium innocuum. Immunol Lett 1997; 58:25-8. [PMID: 9436465 DOI: 10.1016/s0165-2478(97)02715-6] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Segmented filamentous bacteria (SFB) are known to stimulate the mucosal immune system. Here, the effect of SFB on oral booster immunization with ovalbumin was investigated. Mice mono-associated with SFB or Clostridium innocuum were sensitized by intraperitoneal administration of 100 micrograms ovalbumin with Freunds complete adjuvant. After 4 weeks, mice received 80 mg ovalbumin orally. A maximum IgA response was found 5 days after this booster immunization. Comparison of mice with SFB and mice with C. innocuum revealed a much higher level of IgA in the gut lumen and more IgA secreting cells in the lamina propria of the SFB-associated mice. However, no differences between both groups of animals were found in specific levels of IgA secreting cells or luminal IgA against ovalbumin. It is concluded that there is no enhancing effect of SFB after booster immunization when mice are primed intraperitoneally with ovalbumin.
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Affiliation(s)
- J Snel
- Central Animal Laboratory, University of Nijmegen, The Netherlands
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23
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Dong JF, Detta A, Bakker MH, Hitchcock ER. Direct interaction with target-derived glia enhances survival but not differentiation of human fetal mesencephalic dopaminergic neurons. Neuroscience 1993; 56:53-60. [PMID: 8232917 DOI: 10.1016/0306-4522(93)90561-s] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Regulation of the developing nervous system involves attraction, guidance and modification of innervating neurons by target cells through diffusible and membrane-related factors. The trophic effects from specific cell types remain to be investigated and characterized. In a series of experiments in which human fetal mesencephalic dopaminergic cells were co-cultured with target or non-target neurons or glial cells in direct or contiguous contact, we demonstrate that striatal glial cells (target-derived glia) can enhance dopaminergic neuron survival by up to 400% compared to either non-target cell co-cultures or mesencephalic controls. When in direct contact with striatal neurons, a greater proportion of dopaminergic neurons had a more differentiated morphology. The enhancement of dopaminergic neuron survival by target-derived glia appears to be mediated both by direct contact, possibly through target membrane-specific phenomena, and by diffusible substances, whereas non-target glia appear to exert the trophic effects predominantly through the latter mechanism. The finding that target neurons influence mainly dopaminergic neuron differentiation and target glia their survival indicates multiple, target cell type-specific regulation of innervating neuron development. These findings also have relevance to the establishment of neuronal cultures for neural transplantation.
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Affiliation(s)
- J F Dong
- Department of Neurosurgery, University of Birmingham, Midlands Centre for Neurosurgery and Neurology, Smethwick, U.K
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24
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Klaasen HL, Koopman JP, Van den Brink ME, Bakker MH, Poelma FG, Beynen AC. Intestinal, segmented, filamentous bacteria in a wide range of vertebrate species. Lab Anim 1993; 27:141-50. [PMID: 8501895 DOI: 10.1258/002367793780810441] [Citation(s) in RCA: 105] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Segmented, filamentous bacteria (SFBs) form a group of bacteria with similar morphology and are identified on the basis of their morphology only. The relationships of these organisms are unclear as the application of formal taxonomic criteria is impossible currently due to the lack of an in vitro technique to culture SFBs. The intestine of laboratory animals such as mice, rats, chickens, dogs, cats and pigs is known to harbour SFBs. To see whether this extends to other animal species, intestines from 18 vertebrate species, including man, were examined. SFBs were detected with light microscopy in the cat, dog, rhesus monkey, crab-eating macaque, domestic fowl, South African claw-footed toad, carp, man, laboratory mouse and rat, wood mouse, jackdaw and magpie. These results suggest that non-pathogenic SFBs are ubiquitous in the animal kingdom. Among apparently identical animals, there was considerable variation in the degree of SFB colonization. It is suggested that SFB colonization could serve as a criterion of standardization of laboratory animals.
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Affiliation(s)
- H L Klaasen
- Central Animal Laboratory, Catholic University of Nijmegen, The Netherlands
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25
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Klaasen HL, Van der Heijden PJ, Stok W, Poelma FG, Koopman JP, Van den Brink ME, Bakker MH, Eling WM, Beynen AC. Apathogenic, intestinal, segmented, filamentous bacteria stimulate the mucosal immune system of mice. Infect Immun 1993; 61:303-6. [PMID: 8418051 PMCID: PMC302719 DOI: 10.1128/iai.61.1.303-306.1993] [Citation(s) in RCA: 177] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
Segmented filamentous bacteria (SFBs) are apathogenic autochthonous bacteria in the murine small intestine that preferentially attach to Peyer's patch epithelium. SFBs have never been cultured in vitro. We have studied the effects of SFBs on the immune system of the host. Mice monoassociated with SFBs were compared with germ-free mice and with mice without SFBs but with a specific-pathogen-free (SPF) gut flora. SFBs versus no microbial flora raised the number of lymphoid cells in the lamina propria of the ileal and cecal mucosa, raised the number of immunoglobulin A (IgA)-secreting cells in the intestinal mucosa, produced elevated IgA titers in serum and intestinal secretions, and enhanced the concanavalin A-induced proliferative responses of mesenteric lymph node cells. The SPF flora had effects similar to but less pronounced than those mediated by SFBs. The results indicate that SFBs stimulate the mucosal immune system to a greater extent than do other autochthonous gut bacteria.
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Affiliation(s)
- H L Klaasen
- Central Animal Laboratory, Catholic University, Nijmegen, The Netherlands
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26
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Klaasen HL, Peters B, Koopman JP, Poelma FG, van den Brink ME, Bakker MH, Beynen AC. Different degree of ileal colonization by segmented, filamentous bacteria in two strains of mice. J Exp Anim Sci 1992; 35:103-9. [PMID: 1295575] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Segmented, filamentous bacteria (SFBs) are autochthonous, apathogenic inhabitants of the ileum of various animal species. Outbred Swiss (Cpb:SE) mice have significantly higher degrees of SFB colonization than do inbred BALB/c mice. The present studies were carried out to identify determinants of this strain difference. In a cross-fostering experiment it was shown that SFB colonization of the pups is determined by the strain of the pups themselves rather than by the strain of the nursing dam. Thus, maternal effects may not be involved in SFB colonization. In a cross-infecting experiment using germ-free and SFB-positive animals of the two mouse strains, it was found that ileal SFB colonization is determined by host characteristics rather than by origin of the SFBs. Thus, SFBs that are specific for a given mouse strain may not exist in the two strains of mice. It is concluded that the mouse strain difference in SFB colonization is determined by host characteristics, which probably have a genetic basis.
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Affiliation(s)
- H L Klaasen
- Central Animal Laboratory, Catholic University of Nijmegen, The Netherlands
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27
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Bakker MH, McKernan RM, Wong EH, Foster AC. [3H]MK-801 binding to N-methyl-D-aspartate receptors solubilized from rat brain: effects of glycine site ligands, polyamines, ifenprodil, and desipramine. J Neurochem 1991; 57:39-45. [PMID: 1828832 DOI: 10.1111/j.1471-4159.1991.tb02096.x] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The N-methyl-D-aspartate (NMDA) receptor is thought to contain several distinct binding sites that can regulate channel opening. In the present experiments, the effects of ligands for these sites have been examined on [3H]MK-801 binding to a soluble receptor preparation, which had been passed down a gel filtration column to reduce the levels of endogenous small-molecular-weight substances. Glycine site agonists, partial agonists, and antagonists gave effects similar to those observed in membranes [EC50 values (in microM): glycine, 0.31; D-serine, 0.20; D-cycloserine, 1.46; (+)-HA-966, 4.06; and 7-chlorokynurenic acid, 1.81]. Spermine and spermidine enhanced [3H]MK-801 binding to the soluble receptor preparation (EC50, 4.3 and 20.1 microM, respectively), whereas putrescine and cadaverine gave small degrees of inhibitions. When spermine and spermidine were tested under conditions where [3H]MK-801 binding approached equilibrium, their ability to enhance [3H]MK-801 binding was much reduced, a result suggesting that the polyamines increase the rate to equilibrium. Putrescine antagonised the effects of spermine. Ifenprodil reduced [3H]MK-801 binding under both equilibrium and nonequilibrium conditions, although the high-affinity component of inhibition described in membranes was not observed. Ifenprodil antagonised spermine effects in an apparently noncompetitive manner. Desipramine was able to give total inhibition of specific [3H]MK-801 binding under nonequilibrium conditions with an IC50 of 4 microM, and this value was unaltered when [3H]MK-801 binding was allowed to reach equilibrium. These results suggest that the sites mediating the effects of glycine and its analogues, polyamines and desipramine are integral components of the NMDA receptor protein.
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Affiliation(s)
- M H Bakker
- Merck Sharp and Dohme Research Laboratories, Neuroscience Research Centre, Harlow, Essex, England, U.K
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28
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Cornelissen JM, van den Brink ME, Bakker MH, Koopman JP. Cloacal microflora of healthy hornbills, toucans and aracaris. Tijdschr Diergeneeskd 1991; 116 Suppl 1:84S-85S. [PMID: 2048092] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Affiliation(s)
- J M Cornelissen
- Central Animal Laboratory, Catholic University, Nijmegen, The Netherlands
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29
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Bakker MH, Foster AC. An investigation of the mechanisms of delayed neurodegeneration caused by direct injection of quinolinate into the rat striatum in vivo. Neuroscience 1991; 42:387-95. [PMID: 1680225 DOI: 10.1016/0306-4522(91)90383-y] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Injection of the N-methyl-D-aspartate receptor agonist quinolinate, or N-methyl-D-aspartate itself, into the rat brain produces neurodegeneration which can be prevented by N-methyl-D-aspartate receptor antagonists administered up to 5 h after excitotoxin injection. The present study was designed to investigate aspects of the mechanisms involved in this delayed form of neurodegeneration. Following its injection into the rat striatum, extracellular levels of [3H]quinolinate were monitored using a microdialysis probe located 1 mm from the site of injection. Peak concentrations were observed 10-20 min after injection and [3H]quinolinate levels decayed in a biexponential fashion, the initial component having an apparent t1/2 of 13.7 +/- 5.2 min (n = 3). Estimations of the extracellular concentrations of quinolinate after an injection of 200 nmol indicated a peak level of 13.7 +/- 6.0 mM (n = 3) at 10-20 min which declined to 1.2 +/- 0.13 mM (n = 3) by 2 h and substantial levels were present up to 5 h, the period over which N-methyl-D-aspartate receptor antagonists are effective in this model. Administration of dizocilpine at 1, 2, 3 or 5 h after injection of 100, 200 or 400 nmol quinolinate resulted in a similar temporal profile of neuroprotection, as assessed by measuring the activities of choline acetyltransferase and glutamate decarboxylase in striatal homogenates, which was independent of the degree of neurodegeneration produced by the different excitotoxin doses. Overall, these results suggest that the neuronal degeneration caused by quinolinate in vivo is critically dependent upon events occurring after the initial peak of excitoxin levels in the extracellular space.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- M H Bakker
- Merck Sharp and Dohme Research Laboratories, Neuroscience Research Centre, Harlow, Essex, U.K
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